强水敏稠油油藏火烧驱油开发试验效果评价——以王庄油田郑408块沙三段油藏为例

Application evaluation on in-situ combustion in strong water sensitivity heavy oil reservoir-case of Zheng 408 block,Sha III reservoir of Wangzhuang oilfield

王庄油田郑408块沙三段油藏为强水敏性的砂砾岩稠油油藏。选择该块开展火烧驱油先导试验,以加快储量动用,改善开发效果。为研究地下燃烧状况,利用新完钻冷冻保型取心井的常规物性、地化指标、地层矿物分析等实验数据,通过室内物理模拟,对开发效果进行评价,提出平面上可将火烧区划分为已燃区、燃烧前缘区(结焦区)、富油区(油墙)、剩余油区等4个区。不同区带油气各种参数存在较大差异,据此初步建立了利用岩心分析成果评价火烧驱油效果的方法。注气速度是影响研究区火烧驱油开发效果的主要因素,加大注气速度后,有望提升燃烧带平均峰值温度,使燃烧带在平面上得到拓展,有可能重新形成油墙,实现真正的火烧驱油。

In order to improve the development performance of the heavy oil conglomerate reservoir with high water sensitivity,an in-situ combustion test has been implemented in this block to study and evaluate the in-situ combustion performance underground.In this paper,various experiment data from freezing coring,such as physical property,geochemistry index,and stratum mineral,have been utilized to evaluate the development performance of this kind of reservoir through the physical modeling test in laboratory.Herein,it is also proposed that the combustion surface can be divided into four zones:burned out zone,combustion front,rich oil zone,remaining oil zone,and the parameters between zones are variable;in addition,a series of methods to evaluate the development performance of the in-situ combustion by means of core analysis are established.As gas injection velocity is the key factor affecting the performance of in-situ combustion,the average peak temperature is expected be elevated so as to enlarge the combustion zone on plane provided that the gas injection velocity is enhanced.Thus,it may give rise to a new oil rich zone and make the in-situ combustion feasible.